This program project (P01) explores the question of whether different tobacco control policies (e.g., product labeling, smoke-free policies, price and taxation, and product regulation) are relatively consistent or inconsistent in effectiveness across different countries with varying incomes and cultures. The proposed research builds upon the work started by the International Tobacco Control Policy Evaluation consortium (referred to as the ITC Project), which has been supported in part by our Transdisciplinary Tobacco Use Research Center grant (TTURC - P50 CA111236). The ITC Project was established with the aim of applying rigorous evaluation methods to try to understand the impact of the tobacco control policies implemented as part of the Framework Convention on Tobacco Control (FCTC). The strength of the ITC Project has been its unique design utilizing multiple country comparisons, longitudinal cohorts of smokers tracked annually, and a pre-specified, theory-driven mediational model to test hypotheses about the anticipated effects of a given tobacco control policy. Each of the three projects in this application incorporate measures and methods to assess the impact of agent, host, and environmental factors on tobacco use behaviors with slight variations in approach and emphasis. Project 1 examines the relative consistency of different tobacco control policies measured at the population level across a diverse group of 18 high and low and middle-income countries (LMICs). Project 2 extends the work of Project 1 within the area of tobacco packaging and labeling with a focus upon building the evidence for novel policies in LMICs. Project 3 explores how tobacco products differ between high and LMICs, how policies impact product features, and how innate host characteristics such as nicotine metabolism interact with product features to influence tobacco use behaviors. Collectively, the findings from this P01 will help define how different tobacco control policies work, the generality of effects between and within countries, and ultimately inform governments about the need to tailor policy interventions to achieve maximum effectiveness during the next critical five year period of FCTC policy implementation.